This study explores the use of atomically thin two-dimensional (2D) transition-metal dichalcogenides (TMDCs), specifically WS₂, for synaptic transistors in neuromorphic computing. Niobium (Nb) atoms were substitutionally doped at the W sites in WS₂ to enhance the switch ratio. The resulting synaptic transistor devices exhibited a significantly improved switch ratio (10³), 100 times greater than undoped WS₂ devices. The Nb atoms facilitated electron trapping and detrapping, effectively simulating synaptic potentiation, inhibition, and learning processes. The Nb-WS₂ synaptic transistor achieved 92.30% recognition accuracy on the MNIST handwritten digit dataset.